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The best that can be said for evangelicals in the US is that they are not the most disliked religious group in the country.
Yet.

Based on current trends, however, they will be less popular than Muslims and atheists by 2019 or 2020.
This forecast isn’t farfetched; 2017 polling data showed that Canadians would be more likely to vote for a transgender person or an atheist than an evangelical. Additionally, when looking at the Pew data by age group, evangelicals are already on a statistical par (i.e. within the survey margin of error) with atheists and Muslims.

In addition to being seen as “antihomosexual,” “judgmental,” “hypocritical,” and “too involved in politics,” evangelicals are known for taking unpopular religious stances on many issues, including gun control (Jesus wants you to have a gun), climate change, and birth control.
Most proposals to charge women who have abortions with murder have come from evangelicals. They are also seen as particularly hostile to science – and social sciences in particular. 58% of Republicans see colleges and universities as having a negative impact on the country.
These stances have a generational gap, wherein young people are much more likely to support gun control, climate change theory, and government funding for birth control coverage.
Market Competition
As demonstrated above, the primary competition in the market for being a church-going evangelical are other churches, or simply not going to church. There isn’t nearly the life penalty for leaving your church that there used to be, as the US religious landscape has become both more heterogenous and secular.
Finding a community of some sort, even if a secular one, offers an alternative to many. Additionally, other communities can have less expectation of putting money into them, and certainly less than 10% of gross income.
When church is frequently seen by Millennials as boring, irrelevant, shallow, antagonistic to science, simplistic, out of touch with reality, exclusive, and unable to deal with doubt or questions of the faith, is it any wonder that they seek out other activities that better suit them – even if that’s sitting on the couch and watching Netflix on Sunday mornings?